A decayed carcass accidentally netted by a Japanese trawler
near New Zealand in 1977 has often been claimed by
creationists and others to be a likely plesiosaur or
prehistoric "sea-monster." Plesiosaurs were a group of
long-necked, predatory marine reptiles with four paddle-like
limbs, thought to have gone extinct with the dinosaurs
about 65 million years ago. However, several lines
of evidence, including lab results from tissue samples taken
from the carcass before it was discarded, strongly point to
the specimen being a shark, and most likely a basking shark.
This should not be surprising, since basking sharks are known
to decompose into "pseudoplesiosaur" forms, and their carcasses
have been mistaken for "sea-monsters" many times in the past.
Unfortunately, the results of scientific studies on the carcass
data received less media attention than the early sensational
reports, allowing widespread misconceptions about this case
to continue circulating. Therefore, a thorough review
of its history and the pertinent evidence is warranted.

On April 25, 1977, a fishing vessel named the Zuiyo-maru
of the Taiyo Fishery Company Ltd. was trawling for mackerel about
30 miles east of Christchurch, New Zealand, when a large
animal carcass became entangled in its nets at a depth
of about 300 meters (almost 1000 feet). As the massive
creature, weighing about 4000 pounds, was drawn toward the ship
and then hoisted above the deck, assistant production manager
Michihiko Yano announced to the captain (Akira Tanaka), "It's
a rotten whale!" However, as Yano got a better look at
the creature, he became less sure. About 17 other crew
members also saw the carcass, some of whom speculated that
it might be a giant turtle with the shell peeled off. However,
no one on board could say for sure what it was (Aldrich 1977;
Koster 1977).

Figure 1.
Four of the photographs taken by Michihiko Yano aboard the
Zuiyo-maru on April 25, 1977.
A, B. Two front views of the carcass. These were the photos
that inspired many to view the carcass as plesiosaur like.
C. The only clear photograph of the back of
the carcass, showing an apparent dorsal fin and myocommata
along the spine (see Figure 5).
D. The carcass on the deck, with
the anterior end toward the right. A fifth photograph
(not shown) is an almost identical view of the carcass
on the deck, and provides no additional information.

Despite the possible scientific significance of the find,
the captain and crew agreed that the foul-smelling corpse
should be thrown overboard to avoid spoiling the fish catch.
However, as the slimy carcass was being maneuvered over
the ship in preparation for disposal, it slipped from its
ropes and fell suddenly onto the deck. This allowed the
39 year old Yano, a graduate of Yamaguchi Oceanological
high school, to examine the creature more closely. Although
he was still unable to identify the animal, Yano felt it
was definitely unusual, prompting him to take a set of measurements,
along with five photographs using a camera borrowed from a shipmate.
The total length of the carcass measured 10 meters (about
33 feet). Yano also removed 42 pieces of "horny fiber" from
an anterior fin, in hopes of aiding future identification
efforts. The creature was then released over the side and
sank back into its watery grave. All of this took
place within about an hour (Koster 1977). About two months
later Yano made a sketch of the carcass, which unfortunately
conflicts with some of his own measurements, photographs,
and statements (discussed later).

Figure 2.
Figure 2. Sketch of the Zuyiyo-maru carcass, made my Michihiko Yano two months
after carcass was examined and thrown overboard. Sketch and translations appeared in
the Collected Papers of the Carcass of an Unidentified Animal Trawled Off New Zealand
by the Zuiyo-maru, 1978. Major body segment measurements difficult to see in the
drawing: Overall length: 10000 mm, head length: 450 mm, neck length: 1,500 mm.

Translations:
A. Capture of a Nessie-like carcass. Trawled on April 25, 10:00 am at 43 deg. 57.5 min.
S, 173 deg. 48.5 min. E [sic]. B. At the sea off New Zealand; Zuiyo-maru. C. 1. Red
muscles remaining on the back of the trunk, overlaid by fat tissues. 2. There are 40-50
pieces of transparent, nylon-like cartilages roundish in cross section, around the tips and
limbs. D. 3. Judging from the state of putrefaction, the animal may have been alive until
about one month before acquisition. 4. Internal organs in the abdomen are damaged,
eaten by worms or fish. 5. The lower jaw has been lost. E. Front view of the head (300
mm). F. Well skeletonized. G. Probably nostrils [sic]. H. Diameter of the [neck
vertebral bone (200 mm). I. Red muscles; fat layers on them. J. Cross section of the
tail. K. Cross section of the back bone (150 mm). L. No internal organs in the
abdomen. M. Length. N. Diameter [of horny fibers?]. O. Length [of fibers] (200-
300 mm).

When Yano returned to Japan on a different boat on June 10th,
1977, he promptly had his photos developed in the fishery's
darkroom. Company executives were fascinated with the photos,
some of which did appear to show an unusual animal with a
long neck and small head. Local scientists were asked to
look over the photos, and remarked that they had never seen
anything like it (Koster 1977). Some speculated that it
might be some kind of prehistoric creature such as a
plesiosaur.

On July 20, 1977, as excitement and speculation about the
find began to spread, officials from the fish company
held a press conference to publicly announce their mysterious
discovery. Although scientific analysis of the tissue
samples and other data had not yet been completed, company
representatives played up the sea-monster angle. The same
day several Japanese newspapers published sensational front-page
accounts of the find, soon followed by many other radio and
television stories throughout Japan (Sasaki 1978). Although
some Japanese scientists remained cautious, others
encouraged the plesiosaur idea. Professor Yoshinori
Imaizumi, director of animal research at Tokyo National Science
Museum, was quoted in the Asahi Shimbun newspaper as
saying, "It's not a fish, whale, or any other mammal...
It's a reptile, and the sketch looks very like a plesiosaur.
This is a precious and important discover for human beings.
It seems to show these animals are not extinct after all."
(Koster 1977). Tokio Shikama of the Yokohama National
University also supported the monster theme, stating, "It
has to be a plesiosaurus. These creatures must still roam
the seas off New Zealand feeding on fish." (Wire Service
Reports, 7/25/77, reported in Aldrich 1977).

Meanwhile, American and European scientists interviewed
about carcass mystery generally downplayed the sea-monster
theory, as reported by a number of newspapers and wire services
(Denver Post, 7/21/77; Washington Post, 7/22/77;
Boston Globe, 7/22/77); New York Times, 7-24-77;
UPI, 7/24/77; New Scientist 7-28-77).
Paleontologist Bob Schaeffer at the American Museum in New
York noted that every ten years or so a carcass is claimed
to be a "dinosaur" but always turns out to be a basking
shark or adolescent whale. Alwyne Wheeler of the British
Museum of Natural History, agreed that the body was probably
a shark. Explaining that sharks tend to decompose in an
unusual manner (addressed further below), Wheeler added,
"Greater experts than the Japanese fishermen have been foiled by
the similarity of shark remains to a plesiosaur"
Other western scientists offered their own interpretations;
Zoologist Alan Fraser-Brunner, aquarium curator at the
Edinburgh Zoo in Scotland, suggested the body was a
dead sea lion (Koster 1977), despite the creature's immense
size. Carl Hubbs, of the Scripps Institute of Oceanography in
Jolla, California, felt it was "probably a small whale...so
rotten that most of the flesh was sloughed off"
George Zug, curator of reptiles and amphibians at
the Smithsonian Institute, proposed that the creature was
a decayed leatherback turtle (Aldrich 1977).

The divergence among early scientific opinions in this case
might be partly due to the fact that many biologists and
zoologists are used to working with complete,
fresh specimens rather than badly decomposed carcasses (or worse,
photos of such), in which both external and internal organs can
be quite different from their appearance in living animals
(Obata and Tomoda, p 46).

On July 25 1977, Taiyo Fish Company issued a preliminary report
on biochemical tests (using ion-exchange chromatography) on
the tissue samples. The report stated that the horny fiber
sampled from the carcass was "similar in nature to the fin rays
a group of living animals." The "living animals" referred to
were sharks; however, the report failed to state this plainly, leading
to further confusion by the Japanese media (Sasaki 1978) and the
continued spread of monster mania. Toy manufacturers began
gearing up to make wind-up models of the beast, while the
company which made Yano's borrowed camera developed a
whole advertising campaign around his "sea-monster" photos.
Dozens of fishing vessels from Japan, Russia, and Korea were reportedly
streaming toward New Zealand in hopes of resnagging the hastily
discarded creature. Bubbling with excitement, one Japanese
citizen confided that he thought sea-monsters were imaginary
creatures but "danced when I read in the newspaper that it was
still alive!" (Koster 1977). The Japanese government even
issued a new postage stamp (Figure 3) featuring a picture of a
plesiosaur. Not since Godzilla had a monster so overtaken
Japan.

Figure 3.
Commemorative Japanese stamp issued Nov. 2, 1977 in the
wake of the sea-serpent hysteria, showing a long-necked
plesiosaur and the National Science Museum.

The carcass controversy continued to make appearances in the popular
press in America, but with less sensationalism. On July
26, 1977 The New York Times reported that professor Fujio Yasuda,
who initially promoted the carcass resembled a plesiosaur,
acknowledged that initial chromatography tests showed a
profile of amino acids closely resemembling a control sample from a
blue shark. An August 1, 1977 Newsweek article briefly
discussed the "South Pacific Monster" without taking sides.
A few months later a more detailed article by John Koster (1977)
appeared in Oceans magazine. This account evidently
the basis for many subsequent reports, many of which embellished
or oversimplified various aspects of the story. Koster mentioned
the preliminary tissue results and comments by western scientists
supporting the shark interpretation, but also quoted Yano and others
suggesting that the issue was not yet settled. Koster
himself suggested that the small size of the creature's head,
well-defined spinal column, and the lack of dorsal fin, did
not fit the shark identification.

Soon news of the controversial carcass also came to
the attention of some strict creationists, who suggested that
the "likely plesiosaur" supported their young-earth position
(Swanson 1978; Taylor 1984; Peterson 1988). After all,
they seemed to imply, if a creature supposedly extinct for
millions of years can turn up in a fishing net, how can
we trust anything geologists tell us?

However, even if a modern plesiosaur were confirmed, it would not
threaten the concept of evolution. After all, many other modern
animal groups existed during the Mesozoic Era, such as crocodiles,
lizards, snakes, and various fish. Most of these groups are
well represented in the fossil record leading to the
present time, but some creatures, such as the
Coelacanth and
Tautara were once thought to have been extinct
for tens of millions of years, only to be later found alive and
little changed in modern times. These cases emphasize the
incompleteness of the fossil record and the remarkable stasis of
some animal groups, but are not grounds for upheavals in
evolutionary thought. Nevertheless, the discovery of a modern
plesiosaur would certainly be a stupendous scientific find
in its own right, confirming that long-necked "sea serpents"
were not just long-extinct creatures or the stuff of sailor's myths, but
real "living fossils." Unfortunately, a more thorough
examination of the evidence would convincingly refute the
plesiosaur interpretation.

As mentioned, some scientists believed from the start that
the carcass in question was probably a shark, based on their
knowledge of basking shark decay, and similar "sea serpent"
carcass incidents of the past. The basking shark,
Cetorhinus maximus, is the second largest fish in the
sea (surpassed only by the whale shark). It can grow
to more than 30 feet in length, and specimens over 40 feet
have been reported (Soule 1981; Freedman 1985; Dingerkus 1985).
However, this gentle giant is harmless to humans. It feeds
by filtering plankton (mostly tiny crustaceans) through its large gill
rakers as it swims lazily just under the water's surface with
huge mouth agape. When the basking shark decays, the jaws
and loosely attached gill arches often fall away first,
leaving the appearance of a long neck and small head
(see Figure 4).
All or part of the tail (especially the lower half which
lacks vertebral support) and/or the dorsal fin may
also slough away before the better supported pectoral and
pelvic fins, creating a form that superficially resembles
a plesiosaur (Huevelmans 1968; Burton & Burton 1969;
Cohen 1982; Bright 1989 Ellis 1989). Some have called
such remains "pseudoplesiosaurs" (Cohen 1982), although one
might also dub them "plesiosharks"

Figure 4. Basking shark and "pseudoplesiosaur"
A. Basking shark in closed-mouth profile.
B. Basking shark while feeding.
C. Decomposed basking shark presenting a
plesiosaur-like shape. Scale bar shows that a
10 meter basking shark carcass with tail
lost would have essentially the same body
proportions as those indicated in the Zuiyo carcass (Figure 2). The
carcass head and neck combined were measured at 1.95 m long
and the tail 2.0 m, making the unmeasured torso (mid section)
6.05 m by calculation.

As recounted by renowned cryptozoologist Bernard Heuvelmans
(1968), over a dozen supposed "sea serpent" carcasses of
years past were later shown to be definite or probable
shark carcasses--in most cases basking sharks. These
include (but are not limited to), the famous "Stronsa Beast"
of Orkney Islands, England (1808), the Raritan Bay
carcass of New Jersey (1822), the Henry Island, British
Columbia carcass (1934) and the Querqueville monster, France,
also in 1934. These were followed by the Hendaye carcass
in France (1951), the New South Wales carcass, (1959), and
two more cases in 1961 (Vendee, France, and Northumberland,
England). In 1970 another supposed "monster" washed up
at Scituate, Massachusetts. This 30 foot beast was
said to look remarkably like a plesiosaur; however, it also
turned out to be a decayed basking shark (Cohen 1982;
Bright 1989). In 1996 yet another supposed sea serpent was
stranded on Block Island, RI. It too has been evaluated
as a probable basking shark, and was nicknamed the "Block
Ness Monster" (Roesch 1996).

Interestingly, basking sharks seem to have a propensity to
mimic sea serpents while alive as well as dead. Often they
feed in groups at or near the surface (hence their name),
sometimes lining up two or more in a row. When they do this,
the dorsal and tail fins protruding from the water can be,
and sometimes have been, mistaken for multiple "humps" and head
of a long-bodied sea-monster (Sweeney 1972; Bright 1989;
Ellis 1989; Perrine 1995).

By the time the Oceans article was going to press,
scientists in Japan had already formed a research team to study
the Zuiyo-maru case more closely. Copies of the carcass
photographs had reached scientists at the Tokyo University
of Fisheries, including its president Dr. Tadayoshi Sasaki,
who proposed a meeting of scientists to study the available
data. Initial meetings were on September 1 and September 19,
1977, attended by over a dozen scientists, including
specialists in biochemistry, ichthyology, paleontology,
comparative anatomy, and other fields. The workers agreed to
avoid publicizing their individual conclusions until the study
was completed (Sasaki 1978).

In July of 1978, a collection of nine papers presenting
the team's findings were published in a report by the Societe
Franco-Japonaise d'Oceanographie. Despite some disagreements
over specific items of evidence, and the view of some workers
that the identification was still uncertain, the majority
opinion was that the carcass was a badly decomposed
shark, and most likely a basking shark (Sasaki 1978).
This conclusion was strongly supported by several lines of
evidence, including studies on the microscopic appearance,
chemical composition and physical properties of the tissue
samples, as well as a number of anatomical considerations,
elucidated below.

Tissue Sample Evidence

-- The horny fibers sampled from the carcass were rigid, needle-like
structures that tapered toward both ends and had a translucent
light-brown color (Kimura, Fujii, and others 1978). Such features
are characteristic of ceratotrichia, the cartilaginous fibers
of shark fin rays. Abe (1978) found that the carcass fibers
and known ceratotrichia from a basking shark "resembled each
other remarkably."

-- Gross amino acid analysis of the carcass samples gave
results that closely matched elastoidin from a known basking
shark. Elastoidin is a collagenous protein known only from
sharks and rays (not reptiles or even other fish). The match
was especially impressive when known basking shark elastoidin was treated
with an antiseptic sodium hypochlorite (NaClO) solution, as were
the Zuiyo-maru samples (Obata and Tomoda 1978, p 52;
Omura, Mochizuki, and Kamiya 1978, p 58). The correspondence was
virtually identical on all 20 amino acids tested (Table 1).
In discussing this "striking similarity," Kimura, Fujii, and others
(1978, p 72) noted that a statistical test called the
"difference index (DI)" gave the extremely low value of .95
indicating a tight match. They also noted that the high
tryosine content (43 and 41 residues for the samples) is
especially characteristic of shark elastoidin as compared
with other collagens, which typically have 5 or less residues.
ceratotrichia.

Table 1. Results of Gross Amino Acid Analysis on the Horny Fiber
from the 1977 Zuiyo-maru Carcass and Known Elastoidin of a basking
Shark (residues/1000 residues). Composition was determined by
JLC-3BC liquid chromatography (JEOL Co. Ltd.). Both samples
had been treated with NaClO. (Kimura, Fujii, and others 1978).

-- The horny fibers from the fin showed a distinctive shrinking to
about 1/3 the original size when heated in water to 63 degrees C, and
gradually reelongated upon cooling. This unique hydrothermal behavior
is characteristic of elastoidin (Kimura, Fujii, and others 1978, p 68).

-- Electron micrographs of the tissue showed numerous parallel
protofibrils, along with a particular banding pattern that is
characteristic of shark elastoidin. Micrographs also revealed a
major periodic striation pattern of 450-500 angstroms, which is
shorter than typical collagens, but which was previously observed
in basking shark elastoidin (Kimura, Fujii, and others 1978).

Kimura, Fujii, and others (1978) concluded that the composite tissue sample
studies indicated that the horny fiber was essentially identical to
known basking shark elastoidin in both its morphology and amino
acid composition. They remarked, "If the horny fiber was pulled
out from an animal belonging to other classes except Chondrichthyes
[sharks and relatives], it should be significantly different...These
results strongly suggest that this unidentified creature is a basking
shark or closely related species (Kimura, Fujii, and others 1978, p 73).

Anatomy

-- The carcass sketch showed six neck vertebrae, viewed as
"seven or so" by Obata and Tomoda (1978), which is reasonably
consistent with Yano's measurements of neck length (150 cm) and
individual vertebra diameter (20 cm). It is also consistent with
sharks. However, 6 to 7 cervical vertebrae is not consistent with
plesiosaurs and other marine reptiles. Even the pliosaurs, also
known as "short-necked" plesiosaurs, have at least 13 neck vertebrae;
the "long necked" plesiosaurs have far more. (Obata and Tomoda, 1978, p 46).

-- The head of the creature was reported to be turtle-like (Obata
and Tomoda, 1978, p 48). This is consistent with the known cranial
remains of a basking shark, which have been specifically
described as resembling a turtle head (Omura, Mochizuki, and Kamiya 1978, p 59).
In contrast, plesiosaurs had more triangular shaped heads that were
not particularly turtle-like (Hasegawa and Uyeno 1978, p 64).

-- Photographs and witnesses confirm the presence of fin rays,
which are possessed by most fish, including sharks. In contrast,
plesiosaurs had bony phalanges as flipper supports, which were not
seen in the carcass (Obata and Tomoda 1978, p 51). The limb bones
shown in Yano's drawing were evidently based on presumption
or pro-plesiosaur bias rather than observation (Omura
and others 1978, p 56; Obata and Tomoda 1978, p 49).

-- One of the photos (Figure 1c) shows an apparent dorsal fin,
as illustrated in Figures 5). Dorsal fins are possessed by
most fish including sharks, but are thought to have been
lacking in plesiosaurs.

-- The V-shaped along the vertebral column (Figure 1c and 5),
and near the pectoral girdle (Figure 1a) were identified as
myocommata by Omura, Mochizuki, and Kamiya 1978, p 56-57).
Myocommata are composed of strong connective tissues between
myomeres, and are found in sharks but not reptiles.

-- The ribs were measured as 40 cm (about 16 inches) long, which
is far too short for plesiosaurs or other marine vertebrates
except sharks (Hasegawa and Uyeno, p 65). Ironically, some have asked
whether the ribs might be too long for a shark, which typically
have very small ribs. But this was an exceptionally large specimen,
and was probably even larger before decomposition. Also, it is
not certain that Yano accurately identified or measured the ribs,
which do not appear in the photos. Perhaps he mistakenly measured
remnant gill arches, myocommata, or muscle furrows, under the
assumption that they corresponded to ribs.

-- As seen in the photos, the anterior fins appears to be
articulated at a right angle to the shoulder, consistent with
sharks but not plesiosaurs (Obata and Tomoda 1978, p 46);
Hasegawa and Uyeno 1978, p 65). The pectoral girdle
is visible between the front fins in Figures 1a and 1b,
and appears broken but is shark-like in shape (Compagno 1997;
Phelps 1997; Roesch 1997).

-- If the carcass were a plesiosaur, the body would be unlikely to bend in
the posture shown in some of the photographs, since the breast bone
would be large and flat. Likewise, the ventral bones of plesiosaurs, which
should have remained if the anterior fins were preserved, are not seen
in the carcass (Hasegawa and Uyeno 1978, p 64).

-- In plesiosaurs, bones of all limbs were situated at the ventral
(lower) portion of the body; therefore, if the creature were a
decayed plesiosaur, it is likely the limbs would have already
been detached from the body (Hasegawa and Uyeno 1978, p 63).

-- At the existing degree of decomposition, a plesiosaur would
probably have retained its upper jaws and teeth (Hasegawa
and Uyeno 1978, p 63), but no teeth were reported in the specimen
carcass (Obata and Tomoda 1978, p 48). A basking shark, however,
is known to easily loose both jaws, and even if it retained the
upper jaw, its extremely tiny teeth could be more easily overlooked.

-- The carcass length was reported as 10 meters (33 feet).
Basking sharks commonly grow to 30 feet more (Dingerkus 1985;
Freedman 1985), and specimens over 40 feet long have been reported
(Heuvelmans 1968; Herald 1975; Soule 1981; Steel 1985).
Some authors indicate they may even grow to 50 or more feet
(Springer and Gold 1989; Perrine 1995; Allen 1996)
The carcass size would also be compatible with a small plesiosaur,
but the body proportions are not (explained below).

-- Although some of Yano's measurements seem surprisingly
round (for example, 2000 mm for the tail and 10000 mm total length),
if we assume they are reasonably accurate, then the body
proportions (approximately 2:6:2 for the head+neck:torso:tail)
are incompatible with any known plesiosaur fossils (Obata
and Tomoda 1978, p 52). In many plesiosaurs the neck is
by the longest section, and in no case is the torso (between
the pelvic and pectoral fins) much longer than the head and neck,
as it is in the carcass. The carcass could have lost some length
through tail loss (discussed below), but the neck to torso
ratio would still be incompatible with plesiosaurs.

-- The carcass body proportions are largely compatible with a
large basking shark carcass, especially one that lost its
tail (compare Figures 5 and 2). Loss of the tail would be likely,
since the wide tail would tend to snap at the narrow juncture during
decay and buffeting in the water. This would explain the blunt
rather than tapering tail end in Yano's sketch. The rostrum (nose
tip) may also have been lost, but would not appreciably affect the
overall body length or proportions. Adding a tail would
mean the shark was closer to 12.5 meters (41 feet) in life, which
would be exceptionally large, but still within the generally accepted
size range of basking sharks. After all, this poor basker may have
died of old age.

The combined anatomical evidence thus strongly indicates a shark and
and effectively rules out a plesiosaur. Obata and Tomoda
(1978, p 52) conclude, "there are no known fossil reptilian
species that agree with the animal under consideration."
Likewise, Hasegawa and Uyeno (1978, p 64) write, "From the
osteological point of view, we conclude that this creature does
not belong to the plesiosaurian reptiles."

Miscellaneous Observations

-- Japanese shark-fin processors, who are thoroughly familiar with
shark carcasses, identified the animal in Yano's photographs
as a shark (Abe 1978).

-- In September 1977, a positively identified basking shark
carcass was stranded at Nemuro, Hokkaido, and showed a
remarkable resemblance to the Zuiyo-maru carcass found only
five months earlier. Describing the September stranding
Omura, Mochizuki, and Kamiya (1978, p 59-60) wrote, "The jaws and
gill-arches were missing, and the cranium had a somewhat
turtle-like appearance...the pectoral and pelvic fins
were damaged at their apexes but still remained. The
results of this experiment undertaken by nature support the view
that the Zuiyo-maru carcass was a giant shark that has lost its
jaws and gill arches."

Summarizing their findings, Hasegawa and Uyeno (1978) state,
"Based on available evidence, we are convinced that this New Zealand
creature is not the "New Nessie," that much of the world was
hoping for, but more than likely a carcass belonging to a
large size shark."

Alleged Inconsistencies

Despite all the evidence pointing to a shark, some purported
inconsistencies with the shark identification were raised in
the 1978 report and elsewhere, and should be reviewed as well.

-- The carcass reportedly smelled like a dead marine mammal, and
lacked an ammonia smell characteristic of shark carcasses
(Hasegawa and Uyeno 1978, p 65). However, it is not known whether all
sharks give off the ammonia smell while decaying, or for how long.
The same authors noted that the lack of ammonia smell could be
due to the extent of skin loss and decomposition, so that
the ammonia from the carcass was washed out by the sea (Hasegawa
and Uyeno 1978, p 65). Also, even when alive, basking sharks
are known to emit a unique, highly offensive odor of their own
(Steel 1985; Ellis 1989) which could have overpowered any ammonia
smell.

-- A white, sticky, fat-like substance covered much of the
carcass (Obata and Tomoda 1978, p 49). Although Niermann (1994,
p 103) and a few others (Hasegawa and Uyeno 1978) considered
this the strongest argument against the shark theory, it is
actually consistent with it. Basking sharks have large
deposits of fat in the white muscle and liver. According to
some authorities they increase fat reserves during the summer
for winter use (Steel 1985; Sims 1997). The animal in question
likely died in late March or early April, which is late summer in
New Zealand. Moreover, one of the Japanese workers (Seta 1978)
explained the phenomena of adipocere formation in decaying
carcasses of sharks and other animals, whereby new fatty material
can be generated during the decay process. Seta indicated
that the whitish, putrid-smelling viscous substance on the
carcass was consistent with adipocere formation. Also,
some of the whitish, stringy material probably consisted of
ligaments and connective tissue (Omura, Mochizuki, and Kamiya 1978, p
56). Such fibrous tissues on other basking shark carcasses
evidently prompted some reports of "sea monster" corposes
with white manes of hair (Heuvelmans 1968; Sweeney 1972).

-- The photographs reportedly show the presence of reddish muscle
under the white material, which Obata and Tomoda (1978, p49) suggest is
compatible with a tetrapod (four legged animal). However,
the presence of reddish muscle is also compatible with a
shark. Sharks like other fish have both white and red
muscle (Fowler 1997; King 1997; Sims 1997). The former
predominates, but fish that swim slowly and steadily like basking
sharks generally have more red muscle than other sharks (Tullis 1997).
Some of the reddish color also could be due to blood residue.

-- The concerns of some authors about the "small head" or "long neck"
(Koster 1977, Yasuda and Taki 1978) are eliminated once one
understands the process of decay in basking sharks. Summarizing
this process, Omura, Mochizuki, and Kamiya (1978, p 59) state, "...a
disproportionately small skull and long, slender neck can be
accounted for by the loss of the jaws and gill-arches in the
course of decomposition of the carcass."

-- Obata and Tomoda (1978, p 48) also suggest that unlike sharks,
in which the nares (nostrils) are situated in the lower surface of
the skull, the carcass had holes that Yano called "probably nares"
at the front end of the cranium. However, the rostrum or anterior
most structure may have been missing, so that the nares could
have been on the lower side and also the "front" of what remained
of the skull, eliminating any inconsistency. Alternatively, what
Yano thought to be nares could have been any of several other
fenestral openings that exist in shark skulls, or new ones created
during decay.

-- Some witnesses denied the presence of a dorsal fin
(Obata and Tomoda 1978). However, even if a dorsal fin were
absent, it could have been rotted away. Second, as
mentioned, one photo does show an apparent dorsal fin
(see Figures 1c and 5) which was evidently overlooked by Yano and
others. Omura, Mochizuki, and Kamiya (1978, p 56) state, "...by a
close examination of the photograph we can clearly
distinguish the base of a dorsal fin, though it had slipped
from the mid-dorsal line." They note that this somewhat
dislocated dorsal fin evidently had partially overlapped the
right pectoral fin, which may account for Yano's description
of the latter as having two sets of horny fibers.

-- Obata and Tomoda (1978, p 49) suggest that the "long,
cylindrical ribs" in the carcass are not found in selachians."
However, as explained earlier, it is not certain that Yano
accurately identified or measured the ribs. Even if he did,
the rib length (40 cm) is more compatible with a large shark
than a plesiosaur. If the creature were a plesiosaur, it would
have had to be a short necked plesiosaur, whose ribs would
be at least triple the reported length (John Martin 1997).

-- The head was said to be quite hard, whereas sharks contain no
bones, only cartilaginous skeletons. However, cartilage in
shark skulls can be quite hard and dense, and basking sharks
have especially well-calcified skeletons (Steel 1985). Also,
as a shark ages, its skull becomes harder and denser. The
size of the carcass clearly indicates an older specimen.

-- The pelvic (hind) fins were said by some of the crewmen to
be similar in size to the pectoral fins, as in a plesiosaur
(Obata and Tomoda 1978, p 49). However, this cannot be
confirmed, since no measurements or photos were taken of the
pelvic fins. Yano and others may have mistaken the
large, draping and dislocated dorsal fin for one of the other fins
(Hasegawa and Uyeno, (1978, p 62). Or, the combination of
the pelvic fins and rear genital claspers created the illusion
of a sizable rear fin (Hasegawa and Uyeno 1978, p 63).
This might explain Yano's comment that the rear fins had an
unusual appearance like that of a seal (Koster 1977). It is also
possible that the pectoral fins decayed somewhat more than the pelvic
fins, reducing their size disparity. Yano himself acknowledged
that to the best of this recollection the front fins were
somewhat larger than the rear (Koster 1977). His sketch
suggests otherwise, but it is known to contain a number of other
inaccuracies, such as bones in the fins that were not really seen.
Noting such problems, Yasuda and Taki (1978) considered
the sketch inherently unreliable, and Obata and Tomoda (1978)
suggest it was influenced by bias. Indeed, by the time Yano
drew the sketch (two months after the netting) the plesiosaur
idea had become popular, and Yano had become something of a
celebrity over it (Koster 1977).

-- Some readers may be wondering if the location of the find was a
problem for the basking shark identification (as hinted at by Yasuda
and Taki 1978). However, basking sharks are known from many
temperate parts of the world, including the waters around New
Zealand (Burton and Burton 1969; Springer and Gold 1989;
Francis 1997). The carcass was thought to have died in an area
somewhat south of the capture site, well within the known range
of basking sharks (Nasu 1978).

Monsters Don't Die Easily

Overall 1978 reports provided strong evidence favoring the
shark identification, and no substantial objections to it.
Even workers authors such as Obata and Tomoda, who initially
supported the plesiosaur idea and emphasized potential
problems for the shark interpretation, acknowledged
that most evidence pointed to a shark and ruled out a
plesiosaur. They stated, stating, "There are no known fossil
reptilian species which agree with the animal in question"
(Obata and Tomoda 1978). Most of the other 1978 report
authors more plainly stated that the evidence strongly
indicated a basking shark or closely related species (Abe, 1978; Hasegawa
and Uyeno 1978; Omura, Mochizuki, and Kamiya 1978; Kimura et
al 1978).

Unfortunately, the 1978 reports received less public attention
than the original "sea-monster" stories. Most popular media
seemed content to simply let the matter drop rather than helping
to set the matter straight with follow-up articles. Likewise,
several monster/mystery writers continued to depict the case as
largely unresolved, including Welfare and Fairley (1980), Soule
(1981), and Bord & Bord (1989). However, some good summaries
of the 1978 research were provided by Cohen (1982), Bright (1989),
LeBlond (1992), and Ellis (1994) who put aside any hopes that the
beast was a plesiosaur, and properly explained that the specimen
evidently represented one of several basking shark carcasses
mistaken as a sea-monster.

Unfortunately, many creationists continued to promote the
plesiosaur interpretation long after 1978, including Ian Taylor
(1984, 1987, 1989, 1996), Paul Taylor (1984, 1987), Baugh (1987),
Peterson (1988), Baker (1988), Dye (1989), Bartz (1990, 1992),
Buckna (1993), and Morris (1993, 1997). Most seemed unaware of the
1978 resarch and reports. Some flatly called the beast a
plesiosaur (Scoggan 1996; Hovind 1996), or "sea-monster"
(Doolan 1994), or "dinosaur" (Hovind 1996) (plesiosaurs
are not dinosaurs).
Even more perplexing were the comments of creationists who did seem
aware of the 1878 work and tissue tests, and yet suggested they
supported the plesiosaur identification. Among the most
troubling statements are the following:

"From photographs, sketches with careful measurements, and flipper
samples for tissue analysis, it had every appearance of being a
plesiosaur or sea-dwelling dinosaur..." (Ian Taylor 1984, 1978)

"Photographs, measurements, and tissue samples all show that it
was probably a plesiosaur." (Paul Taylor 1987).

"Photographs, tissue examinations, and measurements were made by the
Japanese scientists. Their findings point to a descendant of the
plesiosaur" (Baker 1988).

Some even complained that the press was suppressing the
plesiosaur story (Bartz 1992; Scoggan 1996; Taylor 1996),
despite its coverage in dozens of popular books and
articles, and the fact that it was often presented in a
way more favorable to the plesiosaur interpretation than the
evidence warranted.

Recently two creationists have written more accurate but still
incomplete summaries of the case. Niermann (1994) noted that the 1978
studies pointed to a shark, and that basking sharks tend to decay
into plesiosaur-like shapes. Unfortunately, he tucked these comments
into footnotes, while the body of the text encouraged the plesiosaur
interpretation. Todd Wood (1997) acknowledged that the evidence
strongly supports the basking shark conclusion, but listed several
alleged inconsistencies with the shark identification--none of
which stand up to close scrutiny.

As expected, the New Zealand monster story has also drifted
onto the Internet, often in mangled form. Creationists
Kent Hovind (1996) ,
Walter Brown (1996) ,
Bernard Northrup (1997) ,
Paul Smithson (1996), and
Don Patton (1995)
all encourage the plesiosaur interpretation. Brown matter-of-factly
calls the creature a plesiosaur, which he incorrectly calls a sea-going
"dinosaur." He also notes that the carcass had vertebrae,
asserting these are "something not present in many fish,
including sharks." (Of course fish, including sharks, do
have vertebrae). In contrast, Strange Magazine's "globsters"
web site provides fairly accurate
summaries of the Zuiyo-maru carcass and several other
carcass strandings, as does Roesch (1997a).

Recommendations to Future Monster Finders

Before closing, a word of friendly advice is offered to anyone who
might come upon an unidentified sea creature in the future. Although it
is fortunate that Yano thought to take tissue samples, had he
or others on board saved the animal's head or even a vertebra
(which could have been sealed in a bucket or other container
to avoid fish contamination), much time, effort, and speculation
could have been avoided. In most cases even a single skeletal
element would allow scientists to readily identify an unknown
creature. It also would have been wise to take more photos,
including close-ups of the head and other body parts,
rather than just a few distant shots. That these things were
not done suggests that the crew did not even suspect the creature
could be a plesiosaur until others later suggested this. After
all, even among a group of fishermen someone should have realized
that a prehistoric "sea-monster" would be worth incalculably
more both financially and scientifically than a load of mackerel.
As it turned out, there is little doubt that they actually
caught a decomposed shark.

Nevertheless, it is possible that unknown creatures do still
lurk in the ocean depths. As evidence, only five months before the
Zuiyo-maru incident a naval research vessel near Hawaii
accidentally snagged a bizarre, 4.5 meter (15 foot) long shark in
its parachute-like sea-anchor. The curious fish had an
unusually large head and wide, bowl-shaped jaws--features which
soon earned it the nickname "megamouth." Its jaws were filled
with hundreds of tiny teeth, and opened at the top rather than
at the bottom as in most other sharks. Even stranger, the
inside of the mouth seemed to glow with a silvery light.
Apparently megamouth uses its reflective mouth tissue to attract
tiny crustaceans while feeding in deep water, where little
sunlight penetrates. Eventually the odd selachian was given
the scientific name Megachasma pelagios, and was determined
to represent a new species, genus, and family of shark (Welfare
and Fairley 1980; Soule 1981). Coincidentally, the megamouth
is now considered a close relative of the basking shark.

Conclusions

Several lines of evidence strongly indicate that the Zuiyo-maru
carcass was a large shark, and most likely a basking shark,
rather than a plesiosaur. Those giving the opposite impression
have done so by telling only part of the story, or mischaracterizing
portions of the evidence. To help set the record straight, such
authors should correct any misleading statements of the past on
this issue, and refrain from any further suggestions that the
carcass was a likely plesiosaur.

References Cited

Note: The term CPC in the references below
refers to the collection of papers in the following report:
Sasaki T, ed. Collected papers on the carcass of an unidentified animal
trawled off New Zealand by the Zuiyo-maru. Toyko: La Society
franco-japonaise d'oceanographie, 1978.

Abe T. What the giant carcass trawled off New Zealand suggests
to an ichthyologist. In CPC 1978. pp 79-80.

Aldrich HR. Was it a plesiosaur? INFO Journal.
1977; 6(3).

Allen T. Shadows in the sea. New York: Lyons and Burford, Publishers,
1996.

Anonymous (AP Report). Japanese scientist says that sea creature
could be related to a shark species. New York Times 1977 July 26.